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author | Lang Hames <lhames@gmail.com> | 2013-07-16 22:01:40 +0000 |
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committer | Lang Hames <lhames@gmail.com> | 2013-07-16 22:01:40 +0000 |
commit | 82d4215f64dc941f21bbae7ec781367d343387b8 (patch) | |
tree | 6ee20a6b4efb48a307305d4a08f6948919ea2f30 /lib/Target/ARM/ARMBaseInstrInfo.cpp | |
parent | 898788c6bcc2abfe0e1c7b21c14394352963acd6 (diff) | |
download | llvm-82d4215f64dc941f21bbae7ec781367d343387b8.tar.gz llvm-82d4215f64dc941f21bbae7ec781367d343387b8.tar.bz2 llvm-82d4215f64dc941f21bbae7ec781367d343387b8.tar.xz |
Related to r181161 - Indirect branches may not be the last branch in a basic
block. Blocks that have an indirect branch terminator, even if it's not the
last terminator, should still be treated as unanalyzable.
<rdar://problem/14437274>
Reducing a useful regression test case is proving difficult - I hope to have
one soon.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186461 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Target/ARM/ARMBaseInstrInfo.cpp')
-rw-r--r-- | lib/Target/ARM/ARMBaseInstrInfo.cpp | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/lib/Target/ARM/ARMBaseInstrInfo.cpp b/lib/Target/ARM/ARMBaseInstrInfo.cpp index d6701782a4..5d012fcc02 100644 --- a/lib/Target/ARM/ARMBaseInstrInfo.cpp +++ b/lib/Target/ARM/ARMBaseInstrInfo.cpp @@ -295,6 +295,11 @@ ARMBaseInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,MachineBasicBlock *&TBB, if (!isUnpredicatedTerminator(I)) return false; + // Check whether the second-to-last branch is indirect, return + // 'unanalyzeable' here too. + if (I != MBB.begin() && prior(I)->isIndirectBranch()) + return true; + // If there is only one terminator instruction, process it. if (I == MBB.begin() || !isUnpredicatedTerminator(--I)) { if (isUncondBranchOpcode(LastOpc)) { @@ -322,6 +327,8 @@ ARMBaseInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,MachineBasicBlock *&TBB, LastInst->eraseFromParent(); LastInst = SecondLastInst; LastOpc = LastInst->getOpcode(); + if (I != MBB.begin() && prior(I)->isIndirectBranch()) + return true; // Indirect branches are unanalyzeable. if (I == MBB.begin() || !isUnpredicatedTerminator(--I)) { // Return now the only terminator is an unconditional branch. TBB = LastInst->getOperand(0).getMBB(); |